Performance evaluation of routine blood and C-reactive protein analysis using Mindray BC-7500 CRP auto hematology analyzer

BACKGROUND: Mindray’s newly developed BC-7500 CRP auto hematology analyzers can simultaneously measure the routine blood and C-reactive protein (CRP) results, thereby significantly improving the efficiency and quality of clinical examination. This study was designed to evaluate the basic performance of the BC-7500 CRP as well as the performance characteristics of the new measurement mode combines routine blood and CRP. METHODS: Venous whole blood samples with the anticoagulant ethylene diamine tetraacetic acid K2 (EDTA-K2) were collected at the Fujian Medical University Union Hospital according to the guidelines of the American Clinical Laboratory Standards Institute (CLSI) and International Standards Committee for Hematology (ISCH). We analyzed and evaluated the performance of blank counts, carryover contamination rate, precision, comparability, flagging capability, sample stability, and automatic micro-whole blood (MWB) mode analysis in the BC-7500 CRP hematology analyzer. RESULTS: All parameters measured by the BC-7500 CRP showed good blank counts (CRP, 0.008–0.02 mg/L). The carryover contamination rates for each mode combination did not exceed 1%, it indicates a low carryover effect. The CRP showed high precision while the within-laboratory precision is 6.91% and 4.38% in two different levels. Relatively good correlation was found for the routine blood results between the BC-7500 CRP and Sysmex-XN (r=0.99), and CRP result between the BC-7500 CRP and IMMAGE 800 (r=0.99). The sensitivities of abnormal cell flagging for Blast, Immature Gran, and nucleated red blood cell (NRBC) were 93.9%, 91.6%, and 86.7%, while their specificities were 83.9%, 62.7%, and 97.5%. The test results of CRP at room temperature for 24 hours and refrigerated for 48 hours were −0.04% and −2.94%, which showed very stable changes. Also, the automatic micro-whole blood mode performed well (P=0.2014), which was very close to the test results of the automatic mixing test of peripheral blood and the manual mixing of open sampling. CONCLUSIONS: The BC-7500 CRP analyzer provided reliable results on routine blood and CRP, which can meet the testing requirements of routine blood and CRP items in clinical whole blood samples and provide a guarantee for rapid and accurate laboratory diagnosis.